Irish universities could see a funding gap of more than €400m if foreign students cannot travel here for education.
Figures suggest that students from outside the European Economic Area (EEA) generally pay between €9,000 and €25,000 a year to study here.
This can go as high as €54,000, with most students hailing from North America and Asia.
However without this income, Ireland's seven largest institutions will struggle to pay their bills.
Jim Miley is director-general of the Irish Universities Association.
He says it is unlikely many students will be able to travel due to the coronavirus pandemic.
"We're really concerned that significant numbers of international students will not be able to come to Ireland next year - or indeed that Irish students who are due to travel overseas won't be able to go either.
"So it's a huge hit to our sector."
He said universities have tapped other revenue streams, such as renting out accommodation in the summer months.
However these are no longer an option in the short-term.
"In the financial crash, because of the scarcity of State funding, universities built up their other revenues by really growing their number of international students... we're hopeful that in two or three years we can regain that business.
"But we have a real challenge in that sort to medium term.
"So we're talking to Government to say 'look, universities and higher education have played a hugely significant role in helping to fight the pandemic - we think we can play an equally important role in helping with the economic recovery'.
"I think as the effects of the pandemic become clear, all sectors have taken a hit and we're going to have thousands of people who lose their jobs.
"I think what's important to remember is that higher education and research can actually be a really important part of dealing with the outflow from that.
"It's our sector that can help rebuild the skills.
"We'll have lots of people who'll need to up-skill and re-skill; and we need to maintain our competitive edge on research and innovation if we're to attract foreign direct investment companies into Ireland.
"So we think investing, supporting higher education at this critical time is a really important part of the economic recovery".
